Homework Help:
Dynamics Inclined plane

Hi there I was wondering if someone can help me on this attachment I am stuck on question 1.3 and 1.4. This was an experiment to see relationship between sin and gradient I have confidently completed the first two questions but it is the last two questions which are troubling with I am finding it difficult to get a grasp of. Any help or input would be greatly appreciated.

On my first reaction I think that g sin[itex]\Theta[/itex] is the total for the sin[itex]\Theta[/itex] from the total and r2 is the radius of the disc which in this case is 750mm but I don't understand what k2 is?